Rotary spinning chamber for an open-end spinning machine

ABSTRACT

A rotary spinning chamber for an open-end spinning machine. The chamber has a bottom wall secured to a shaft for rotatably driving the spinning chamber, the bottom wall extending substantially perpendicularly to the shaft. A collecting surface is formed adjacent to and surrounding the outer periphery of the inner surface of the bottom wall for collecting fibers fed into the spinning chamber through a fiber feeding conduit. A plurality of air exhaust channels is provided for exhausting the air inside the spinning chamber for reducing the air pressure inside the spinning chamber to create an air flow through the fiber feeding conduit toward the interior of the spinning chamber. The inner surface of the bottom wall gradually bulges in the axial direction of the shaft toward the interior of the spinning chamber as the center of the inner surface is approached, and each of said exhaust channels has the air inlet opening thereof located in the inner surface and the air outlet opening thereof located in an outer peripheral surface of the spinning chamber at a position located radially outwardly of the air inlet opening.

United States Patent [1 1 [111 3,775,957 Kihara et al. Dec. 4, 1973 ROTARY SPINNING CHAMBER FOR AN Primary Examiner-John Petrakes OPEN-END SPINNING MACHINE Inventors: l-lidetoshi Kihara, Fukui; Kanemitsu Tsuzuki, Kariya, both of Japan Assignees: Daiwa Boselsi Kabushiki Kaisha,

Osaka; Kabushiki Kaisha Toyoda Jidoshokki Seisakusho, Kariya, Japan Filed: Apr. 10, 1972 Appl. No.: 242,369

Foreign Application Priority Data Morikawa et al 57/ Attorney-E. F. Wenderoth et al.

57 ABSTRACT A rotary spinning chamber for an open-end spinning machine. The chamber has a bottom wall secured to a shaft for rotatably driving the spinning chamber, the bottom wall extending substantially perpendicularly to the shaft. A collecting surface is formed adjacent to and surrounding the outer periphery of the inner surface of the bottom wall for collecting fibers fed into the spinning chamber through a fiber feeding conduit. A plurality of air exhaust channels is provided for exhausting the air inside the spinning chamber for reducing the air pressure inside the spinning chamber to create an air flow through the fiber feeding conduit toward the interior of the spinning chamber. The inner surface of the bottom wall gradually bulges in the axial direction of the shaft toward the interior of the spinning chamber as the center of the inner surface is approached, and each of said exhaust channels has the air inlet opening thereof located in the inner surface and the air outlet opening thereof located in an outer peripheral surface of the spinning chamber at a position located radially outwardly of the air inlet opening.

4 Claims, 5 Drawing Figures PATENTED BEE 4 I975 sum 3 0F 3 ROTARY SPINNING CHAMBER FOR AN OPEN-END SPINNING MACHINE The present invention relates to a rotary spinning chamber for an open-end spinning machine.

In this type of spinning machine there is provided a rotary spinning chamber serving as a fast-rotating rotor. The rotary spinning chamber comprises a bottom wall secured to a shaft for rotatively driving the spinning chamber and extending substantially perpendicularly to said shaft, a collecting surface formed adjacent to and surrounding an outer periphery of an inner surface of the bottom wall for collecting fibers fed into the spinning chamber through a fiber feeding conduit, and a plurality of air exhaust channels for exhausting the air inside the spinning chamber forreducing the air pressure inside the spinning chamber to create an air flow through said fiber feeding conduit toward inside the spinning chamber.

When such spinning chamber is rotated by means of said driving shaft, the air inside the spinning chamber is exhausted outside the same through the exhaust channels, thusthere is produced a reduced air pressure condition in the spinning chamber. Thisreduced air pressure condition results in an air flow through the fiber feeding conduit toward inside the spinning chamber, and the fibers in the fiber feeding conduit is entrained in the air flow thus created and fedinto the spinning chamber..These fibers fed into the spinning chamber are subjected to a centrifugal force due torotation of the spinning chamber, and forced toward and deposited onto the collecting surface. The fibers deposited on the collecting surface are successively spun into a yarn by being rolled in at the yarn. end. Thus spun yarn is then withdrawn from the spinning chamber through a withdrawing tube. I

In such prior spinning chamber, an air inlet opening of the exhaust channel is located in an inclined surface which forms a recess at the central portionof the inner surface of the bottom wall.

With such construction of the spinning chamber, when the air flowed into the spinning chamber moves toward the air exhaust channels, the short fibersand foreign matter such as dust entrained in the air flow are moved in contact with the inclined surface of said recess and strongly present against said inclined surface by the action of centrifugal force, and due to such pression of the short fibers against said inclined surface, cotton wax is deposited on said inclined surface; The shortfibers and foreign matter pressed successively against said inclined surface are adhered to the cotton wax and gradually accumulated there. As the accumulated mass of such short fibers and foreign matter increases, the centrifugal force thereof also increases, and finally the accumulated mass is stripped off from said inclined surface and thrown toward the collecting surface by the increased centrifugal force.

This brings about a great drawback that the mass of the short fibers and foreign matters thrown to the collecting surface is rolled into the yarn causing yarn breakage, decrease of yarn strength and formation of knobs or lumps in the yarn.

The spinning chamber in current use has another drawback. This drawback consists in that the air exhaust channel has a relatively high air exhaust resistance. That is, since the area of the inlet opening of the air exhaust channel located in said inclined surface is only as large as or slightly larger than the sectional area of the air exhaust channel in a place perpendicular to an axis thereof, the inlet opening present a high resistance against the air flowing into the air exhaust channel.

In view of the above-mentioned drawbacks of the prior spinning chamber, a main object of the present invention is to provide an improved rotary spinning chamber.

More particularly, the object of the present invention is to provide a rotary spinning chamber wherein the inner surface of the bottom wall gradually bulges in the axial direction of the driving shaft toward inside the spinning chamber as the center of said inner surface is approached, and each of the air exhaust channels has its air inlet opening located in said inner surface and its air outlet opening located in an outer peripheral surface of the spinning chamber at a position located radially outwardly of the air inlet opening.

Another object of the present invention is to provide a rotary spinning chamber of the above mentioned nature, wherein the air inlet opening of each air exhaust channelis located in a position lagged from the airinlet opening of the same air exhaust channel as viewed in the direction of rotation of the spinning chamber.

In accordance with the present invention, since the inner surface of the bottom wall is gradually bulged in the axial direction of the driving shaft toward inside the spinning chamber as the center of said inner surface is approached, the short fibers and foreign matter are smoothly moved toward the inlet openings of the air exhaust channels along with the air without being strongly pressed against the inner surface of the bottom wall, thereby the deposition of the cotton wax onto said inner surface is eliminated and accumulation of the short fibers and foreign matter is also prevented.

Furthermore, in accordance with the present invention,since the airinlet opening of each air exhaust channel is located in said bulged inner surface of the bottom wall, the area of the air inlet opening becomes much larger than that of the prior spinning chamber, thereby the resistance against the air flowing into the air inlet opening is substantially decreased.

Furthermore, in accordancewi'th another aspect of the present invention, since the air outlet opening of each air exhaust channel is located in aposition lagged from the air inlet opening of the same air exhaust channel as viewed in the direction of rotation of the spinning chamber, i.e., the air inlet openingis located in advance of the air outlet opening as viewed in the direction of rotation of the spinning chamber, the resistance against the air flow in the air exhaust channel is substantially decreased.

The invention will now be described with reference to the drawings, in which: 5 FIG. 1 is an axial sectional view of a prior rotary spinning chamber, a frame body surrounding the spinning chamber and a closure plate for closing an open side of the spinning chamber;

FIG. 2 is an axial sectional view of an embodiment of the rotary spinning chamber according to the present invention;

FIG. 3 is a perspective view of the spinning chamber as shown. in FIG. 2;

FIG. 4 is an axial sectional view of another embodiment of the rotary spinning chamber according to the present invention; and

FIG. is a plan view of yet another embodiment of the rotary spinning chamber according to the present invention.

Now referring to FIG. 1, there is shown an example of the prior rotary spinning chamber generally designated by the reference numeral l. The spinning chamber 1 comprises a bottom wall ,4 which is secured to a shaft 3 which in turn is rotatably supported from a supporting member 2 through a bearing (unnumbered). The bottom wall 4 extends substantially perpendicularly to the shaft 3 as seen in FIG. 1. The shaft 3 is connected to a suitable driving source to rotatively drive the spinning chamber l. The reference numeral 6 designates an inner surface of the bottom wall 4 which is surrounded by a collecting surface 5 formed at the largest inner diameter portion of the spinning chamber 11 and adjacent to and as a continuation of an outer periphery of said inner surface 6. The spinning chamber 1 further comprises a plurality of air exhaust channel 8 which has its air inlet opening '7 opened into a space inside the spinning chamber and its air outlet opening 9 located in an outer peripheral surface of the spinning chamber 1.

' The top opening of the spinning chamber 1 is closed by a fixed closure 10, to which are attached a fiber feeding conduit 11 and a yarn withdrawing tube 12, the outlet of said conduit 111 being directed toward said inner collecting surface 5. Further, the spinning chamber 1 is surrounded by a frame body 13, and a pipeline 14 connected to a part of the frame body 13 is connected to a suction source (not shown). The rotary spinning chamber, which receives fibers delivered from the fiber feeding conduit llll, functions to form a yarn on the inner collecting surface 5 in known manner. The yarn thus formed, i.e., spun yarn is withdrawn outside the spinning chamber ll through said yarn withdrawing tube 12.

Upon rotation of the spinning chamber 1, the sucking action of the pipeline 14 and the exhaust action of the exhaust channels 8 cooperate to establish a reduced pressure state in the spinning chamber 1, so that there is created an air flow through the fiber'feeding tube 11 toward inside the spinning chamber ii and the fibers in the fiber feeding conduit lll are entrained by the air flow and delivered toward the collecting surface 5. The fibers thus delivered will deposite onto the collecting surface 5 due to the centrifugal force, but the air will flow toward the air inlet openings 7 of the air exhaust channels 8. The air flowing toward said air inlet opening 7 is entraining short fibers and foreign matter therein. As is seen in FIG. 1, the bottom wall 4 of the spinning chamber 1 is centrally provided with a recess 15, which is defined by a flat surface 116 and an inclined surface 16'. The air inlet openings 7 of said air exhaust channels 8 are located in said inclined surface 16'. As a result, by virtue of the facts that the short fibers and foreign matter entrained in the air flow directed from around the inner collecting surface 5 toward the air inlet openings 70f the air exhaust channels 8 are forced to move in contact with said inclined surface 116' and that said short fibers and foreign matter are pressed against said inclined surface to by the action of centrifugal force, the cotton wax is tightly adhered to said inclined surface 16. Thus the short fibers and foreign matter pressed successively against said inclined surface 16 are adhered to the cotton wax. Further, it often happens at said inclined surface 16 that the force of the air flow directed toward said air inlet openings 7, acting on the short fibers and foreign matter, is balanced with the centrifugal force of the short fibers and foreign matter. This also causes adhesion of the fibers and foreign matter onto the cotton wax, thus accelerate the accumulation of the short fibers andforeign matter thereon.

As the accumulated mass of the short fibers and foreign matter becomes larger, the centrifugal force is correspondingly increased and at last said accumulated mass is separated or stripped from the inclined surface 16' and thrown to the inner collecting surface 5 and rolled into the yarn, thus forming the cause of yarn breakage, decrease in yarn strength and formation of knobs or lumps in the yarn. Furthermore, such accumulated mass of the short fibers and foreign matter tends to be caught at the air inlet openings 7 of the air exhaust channels 8 and stays there, decreasing the air exhausting efficiency.

Furthermore, as seen in FIG. 1, the area of the air inlet opening 7 is only slightly larger than the crosssectional area of the air exhaust channel 8 in a plane perpendicular to the axis of the same. Therefore, the air inlet openings 7 of the air exhaust channels 8 present relatively high resistance against the air flowing therethrough, decreasing the air exhausting efficiency.

These drawbacks are overcome by the present invention of which an embodiment is shown in FIG. 2.

Also in FIG. 2, the reference numeral 1 designates a rotary spinning chamber, 3 a drive shaft, 4 a bottom wall, 5 a collecting surface, 6 an inner surface of the bottom wall 4, 8 an air exhaust channel, 7 an air inlet opening and 9 an air outlet opening. And also in this embodiment, the bottom wall 4 of the spinning chamber 1 is secured to the drive shaft 3 substantially perpendicularly thereto.

However a substantial difference resides in that the inner surface 6 of the bottom wall 4 gradually bulges in the axial direction of the driving shaft 3 toward inside the spinning chamber 1 as the center of said inner surface 6 is approachedln other words, the height of the inner surface 6 of the bottom wall 4 as determined from a plane perpendicular to the axis of the driving shaft 3 and passing through the bottom of the collecting surface 5 is largest at the center of said inner surface 6 and graudally decreases toward the collecting surface 5. In this embodiment the bulged inner surface 6 of the bottom wall 4 is constituted by a curved surface of a fixed radius.

Furthermore, said air inlet opening 7 is located in the bulged inner surface 6 of the bottom wall 4 and said air outlet opening 9 is located in an outer peripheral surface of the spinning chamber 1 at a position located radially outwardly of the air inlet opening 7. The air exhaust channel 8 is straight in this embodiment.

As will be noted, the short fibers and foreign matter entrained in the air flowing into the spinning chamber 1 through the fiber feeding conduit 11 are planarly guided along the bulged smooth inner surface 6 toward the air inlet openings 7 of the air exhaust channels 8 so that they can smoothly and easily flow into the air inlet openings 7. There may happen that some of the short fibers and foreign matter pass over the areas between any adjacent air inlet openings 7 and deposit around the center of the inner surface 6 of the bottom wall 4. However, such deposited short fibers and foreign matter are immediately forced directly to the collecting large or into the air inlet openings 7 of the air exhaust channels 8 in the case wherein the centrifugalforce is small, since there is no obstacle against such movements of the short fibers and foreign matter, thus there occurs no accumulation of the short fibers and foreign matter.

In this connection, it should be noted that an edge 7' of the air inlet opening 7 located closer to the center of the inner surface 6 than the other edge 7", is located at a higher level than said the other edge 7 as determined from the plane perpendicular to the drive shaft 3 and passing through the bottom of the collecting surface 5. Therefore, when the short fibers and foreign matter deposited around the center of the inner surface 6 of the bottom wall 4 are forced to move towardthe collecting surface 5 due to large centrifugal force, they pass over said the other edge 7 directly to the collecting surface 5 without engaging with said the other edge 7". When the centrifugal force is small, the short fibers and foreign matter deposited around. thecenter of the inner surface 6 are sucked smoothly into the air exhaust channels 8 through the air inlet openings 7 thereof by a strong air flow flowing into the air exhaust channel 8. Thus in either case, there occurs no accumulation of the short fibers and foreign matter.

Furthermore, the air exhaust channel 8 is directed radially outwardly, the area of the air inlet opening 7 of the air exhaust channel 8 is necessarily substantially larger than; the cross-sectional area of the air exhaust channel 8 in a plane perpendicular to the axis thereof. Thus the area of the air inlet opening 7 is much increased, and therefore, not to mention air, even short fiber and foreign matter can enter the air inlet opening 7 extremely smoothly and easily.

Another embodiment of the present invention is shown in FIG. 4.

This embodiment is almost same as the embodiment shown in FIGS. 2 and 3. Only difference is that the bulged inner surface 6 of the bottom wall 4, in this embodiment, is constituted by a cone shaped surface rather than a curved surface. The perspective view of this embodiment is similar to the one of the first embodiment shown in FIG. 3 except that the shape of the air inlet openings 7 of the air exhaust channels 8 is slightly varied.

This embodiment provides the same advantages or merits as obtainable by the first embodiment shown in FIGS. 2 and 3, i.e., elimination of accumulation of the short fibers and foreign matter on the inner surface 6 of the bottom wall 4, and reduction of resistance of the air inlet openings 7 of the air exhaust channel 8 against the air flowing into the same. This embodiment-provides further advantage or merit that the bulged surface of the cone shape is much easier to produce than the curved bulged surface.

A still further embodiment is shown in FIG. 5.

In this embodiment, the straight air exhaust channel 8 having its air inlet opening 7 located in the bulged inner surface 6 of the bottom wall 4 and its air outlet opening 9 located in the outer peripheral surface of the spinning chamber 1 at a position located radially outwardly of the air inlet opening 7 is inclined from radial direction of the spinning chamber 1 so that the air outlet opening 9 is lagged from the air inlet opening 7 of the same air exhaust channel 8 as viewed in the direction of rotation of the spinning chamber 1. In other 6 words, the air inlet opening 7 is located in advance of the air outlet opening 9 as viewed in the direction of rotation of thespinning chamber.

According to this embodiment, as apparent to those who skilled in the art, the air and the short fiber and foreign matter entrained in the air can pass through the air exhaust channels 8 much easily, and, therefore, the possibility of deposition of theshort fibers and foreign matter onto a rear inner surface of the air exhaust channel8 as viewed in the direction of rotation of the spinning chamber 1, due to the inertia of the short fibers and the foreign matter, is much decreased. Thus the inner surface of the air exhaust channel 8 is always kept in a clean state, enhancing reduction of the resistance against airflow throughthe air exhaust channel 8. t

This advantage or merit is further enhanced by constituting the air exhaust channel 8 by a curved channel which is convex in the direction of rotation of the spinning chamberl. However, it is very difficult to bore such curved air exhaust channel 8 through the bottom wall 4 of the spinning chamber 1. Therefore, more practical straight air exhaust channel 8 which can be easily bored is preferred.

A further advantage or merit obtainable by the embodiment of FIG. 5 resides in that the air inlet openings 7 are directed substantially tangentially relative to the direction of rotation of the spinning chamber 1 so that the air and the short fibers and foreign matter can easily enter into the air exhaust channels 8.

While the principles of the invention have been described above in connection with specific embodiments, it is to be understood that this description is made only by way of example and there can be made variousmodifications within the scope of the present invention. Thus, for instance, the feature of the embodiment shown in FIG. 5 can be: applied to the embodiments shownin FIGS. 2, 3 and What we claim is:

I. A rotary spinning chamber for an open-end spinning machine, comprising a bottom wall secured to a shaft for rotatively driving the spinning chamber and extending substantially perpendicularly to saidshaft, a collecting surface formed adjacentto and surrounding an outer periphery of an inner surface of the bottom wall for collecting fibers fed into the spinning chamber through a fiber feeding conduit, and a plurality of air exhaust channels for exhausting the air inside the spinning chamber for reducing the air pressure inside the spinning chamber to create an airflow through said fiber feeding conduit towardinside the spinning chamber, characterized in that the inner surface of thebottom wallgradually bulges in the axial direction of the shaft toward inside the spinning chamber as the center of said inner surface is approached, and each of said exhaust channels has its air inlet opening located in said inner surface and its air outlet opening located in an outer peripheral surface of the spinning chamber at a position located radially outwardly of t the air inlet opening.

2. A rotary spinning chamber for an open-end spinning machine as claimed in claim 11, characterized in that said bulged inner surface of the bottom wall of the spinning chamber is constituted by a curved surface.

3. A rotary spinning chamber for an open-end spinning machine as claimed in claim 1, characterized in that said bulged innersurface of the bottom wall of the 7 8 spinning chamber is constituted by a cone shaped staris located in a position lagged from the air inlet opening face of the same air exhaust channel as viewed in the direc- 4. A rotary spinning chamber for an open-end spinning machine as claimed in claim 1, characterized in that the air outlet opening of each air exhaust channel tion of rotation of the spinning chamber. 

1. A rotary spinning chamber for an open-end spinning machine, comprising a bottom wall secured to a shaft for rotatively driving the spinning chamber and extending substantially perpendicularly to said shaft, a collecting surface formed adjacent to and surrounding an outer periphery of an inner surface of the bottom wall for collecting fibers fed into the spinning chamber through a fiber feeding conduit, and a plurality of air exhaust channels for exhausting the air inside the spinning chamber for reducing the air pressure inside the spinning chamber to create an air flow through said fiber feeding conduit toward inside the spinning chamber, characterized in that the inner surface of the bottom wall gradually bulges in the axial direction of the shaft toward inside the spinning chamber as the center of said inner surface is approached, and each of said exhaust channels has its air inlet opening located in said inner surface and its air outlet opening located in an outer peripheral surface of the spinning chamber at a position located radially outwardly of the air inlet opening.
 2. A rotary spinning chamber for an open-end spinning machine as claimed in claim 1, characterized in that said bulged inner surface of the bottom wall of the spinning chamber is constituted by a curved surface.
 3. A rotary spinning chamber for an open-end spinning machine as claimed in claim 1, characterized in that said bulged inner surface of the bottom wall of the spinning chamber is constituted by a cone shaped surface.
 4. A rotary spinning chamber for an open-end spinning machine as claimed in claim 1, characterized in that the air outlet opening of each air exhaust channel is located in a position lagged from the air inlet opening of the same air exhaust channel as viewed in the direction of rotation of the spinning chamber. 